In a system such as a digital television or a recorder, an amount of data to be processed is increasing exponentially with increased performance. Therefore, a semiconductor memory mounted in the system is required to have an increased capacity and an improved data transfer rate.
As a semiconductor device to be mounted in such a system, System-on-Chip (SoC) where a logic circuit chip mounted with a memory controller thereon and a memory are stacked in a single chip may be employed, or System-in-Package (SiP) where the logic circuit chip mounted with the memory controller thereon and the memory are stacked to be housed in one package may be employed.
At present, there is a tendency to employ a system using SiP whose manufacturing cost is relatively low. In order to increase the data transfer rate between the memory chip and the logic circuit chip in SiP, Chip-on-Chip (CoC) technology can be used for making flip-chip connection of the chips directly via a micro bump, etc (between the memory chip and the logic circuit chip). By way of example, there is a fan-out type of CoC technique (for example, see Patent Literature 1).
In Patent Literature 1, as shown in FIG. 13, an extension part 202 is provided lateral to a semiconductor chip 201 on a lower stage, and a semiconductor chip 203 is stacked on the semiconductor chip 201 and then comes on an upper stage. On the other hand, in an integrated circuit package 300 of Patent Literature 2, as shown in FIG. 14, integrated circuit dies 304, 306, 308, 310 are stacked on a substrate 302, and upper surfaces of the integrated circuit dies 304, 306, 308, 310 are connected to an upper surface of the substrate 302 by wires 312, 314, 316, 318, respectively. In Patent Literature 2, the integrated circuit dies 304, 306, 308, 310 are of the same size. In Patent Literature 2, as shown in FIG. 15, on an upper surface 402 of one integrated circuit die 420, each of bonding pads 414 provided on one side 410 is re-distributed via a metal wire 416 to one of bonding pads 418 between bonding pads 412 provided on the other side 408.